Per SecureList, a new version of a backdoor trojan for Apple’s OS X operating system takes advantage of an exploit in Microsoft Word to spread.

The latest variant of the attack known as “LuckyCat” was discovered and detailed by Costin Raiu, Kasperskky lab expert. Raiu found that a dummy infected machine was taken over by a remote user who started analyzing the machine and even stole some documents from the Mac.

“We are pretty confident the operation of the bot was done manually — which means a real attacker, who manually checks the infected machines and extracts data from them,” Raiu wrote in a post.

The new Mac-specific trojan, named “Backdoor.OSX.SabPub.a,” uses a Java exploit to infect targeted machine. It spreads through Microsoft Word documents that exploit a vulnerability known as “CVE-2009-0563.”

The new trojan is noteworthy because it stayed undetected for more than a month and a half before it came alive and data was manually extracted from the machine. That’s different from MaControl, another bot used in attacks discovered in February 2012.

There are currently at least two variants of the “SabPub” trojan, which remains classified as an “active attack.” It is expected that new variants of the bot will be released in the coming weeks, as the latest was created in March.

Security on the Mac has been in the spotlight of late as a result of the “Flashback” trojan that infected more than 600,000 Macs worldwide. Apple addressed the issue with a series of software updates last week designed to remove the trojan from affected machines.

The Flashback botnet harvested personal information and Web browsing logs from infected machines. The trojan, which disguises itself as an Adobe Flash installer, was first discovered last September.